Clock/Timing - Clock Generators, PLLs, Frequency Synthesizers

Part Number	Description / PDF	Quantity
CD74HC4046AM Texas Instruments	IC PLL W/VCO 16-SOIC	1514
CDCDLP223PWR Texas Instruments	CLOCK GENERATOR, 300MHZ, CMOS	48000
PLL1707DBQ Texas Instruments	IC 3.3V PLL MULTI-CLK GEN 20QSOP	12710000
CD74HCT4046AMT Texas Instruments	IC PLL W/VCO HS 16-SOIC	811
LMX2433TMX/NOPB Texas Instruments	PLL FREQUENCY SYNTHESIZER	1500
LMK5B12204RGZT Texas Instruments	ULTRA-LOW JITTER SINGLE CHANNEL	0
CDCE18005RGZT Texas Instruments	IC 5/10 OTPT CLOCK/BUFFER 48-QFN	246
CDC7005ZVA Texas Instruments	CDC7005 HIGH PERFORMANCE, LOW PH	13145
LMX2325TMX Texas Instruments	PLL FREQUENCY SYNTHESIZER	7685
PLL1708DBQRG4 Texas Instruments	IC PLL MULTI-CLK GEN DUAL 20QSOP	0
LMX2531LQE1312E/NOPB Texas Instruments	IC PLL FREQ SYNTH W/VCO 36WQFN	0
LMX2531LQ1910E/NOPB Texas Instruments	IC PLL FREQ SYNTH W/VCO 36WQFN	444
CD74HCT7046AMT Texas Instruments	IC PLL W/VCO/LOCK DETECT 16SOIC	245
CDC2536DBR Texas Instruments	CDC2536 3.3V PLL CLOCK DRIVER WI	18000
CDC421A156RGET Texas Instruments	CDC421A156 FULLY INTEGRATED FIXE	4020
CDCEL925PWR Texas Instruments	IC 2PLL VCXO CLK SYNTH 16-TSSOP	1999
CDC421A125RGET Texas Instruments	CDC421A125 FULLY INTEGRATED FIXE	4083
TRF3761-JIRHAR Texas Instruments	PLL FREQUENCY SYNTHESIZER	7500
CDCV857BDGGR Texas Instruments	PLL CLOCK DRIVER	51262
LMK03318RHST Texas Instruments	IC CLOCK GENERATOR PLL 48WQFN	43310000

Clock/Timing - Clock Generators, PLLs, Frequency Synthesizers

1. Overview

Clock and timing ICs are semiconductor devices that generate, regulate, and distribute timing signals in electronic systems. Key components include Clock Generators (produce stable clock signals), Phase-Locked Loops (PLLs, synchronize signals with phase alignment), and Frequency Synthesizers (generate precise frequencies from reference signals). These devices ensure synchronization across components in modern electronics, enabling reliable operation in communication systems, computing devices, and industrial equipment.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Clock Generators	Produce fixed or programmable clock signals with low jitter	Microprocessors, FPGAs, networking equipment
PLLs	Align output signal phase with reference input, enable frequency multiplication	Wireless transceivers, data recovery circuits
Frequency Synthesizers	Generate multiple frequencies from single reference with high precision	5G base stations, satellite communication systems

3. Structure and Components

Typical clock ICs feature: 1) Crystal oscillator interface for reference signal input; 2) Internal voltage-controlled oscillator (VCO); 3) Phase detector and loop filter (PLL components); 4) Programmable dividers; 5) Output buffers. Advanced packages include QFN (4x4mm to 8x8mm) and TSSOP with 8-48 pins. Integration levels vary from single-channel devices to multi-output clock generators with integrated EEPROM.

4. Key Technical Specifications

Parameter	Typical Range	Importance
Frequency Range	1 kHz - 3.6 GHz	Determines application compatibility
Phase Noise	-150 to -120 dBc/Hz	Impacts signal integrity
Jitter (RMS)	50 fs - 1 ps	Critical for high-speed systems
Power Consumption	10-300 mA	Affects thermal design
Temperature Stability	20-100 ppm	Ensures reliability in harsh environments

5. Application Fields

Telecommunications: 5G NR base stations, optical transceivers
Computing: Server motherboards, PCIe clocks
Industrial: Precision test equipment, motor control systems
Automotive: ADAS sensors, infotainment systems
Medical: MRI imaging systems, patient monitoring devices

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
TI (Texas Instruments)	LMX2594	15-GHz wideband PLL with integrated VCO
Analog Devices	AD9548	4-channel clock generator with 0.1 ppb accuracy
STMicroelectronics	CLK2692	Programmable 2-output synthesizer for automotive
Microchip	ZL30264	High-performance network synchronizer

7. Selection Guidelines

Key selection criteria: 1) Required output frequency and voltage levels; 2) Acceptable phase noise/jitter specifications; 3) Number of required outputs; 4) Operating temperature range; 5) Power budget constraints; 6) Integration level (e.g., single-chip vs. discrete VCO solutions). For wireless applications, prioritize low phase noise. For portable devices, emphasize power efficiency.

8. Industry Trends

Future developments include: 1) Higher integration with on-chip EEPROM and multi-phase outputs; 2) Advancement to sub-10fs jitter performance; 3) Development of radiation-hardened variants for aerospace; 4) Adoption of 3D packaging for reduced EMI; 5) Increased use of AI-enabled dynamic frequency scaling. The market is projected to grow at 7.2% CAGR through 2027 driven by 5G and automotive electrification.